73 moon landings? NASA's 'Moon Base User's Guide' reveals the agency's 'most ambitious space project' will be fraught with challenges

NASA wants to speed up its lunar missions and establish a permanent moon base.

NASA has published a "Moon Base User's Guide" detailing the many challenges the agency will need to overcome for it to complete 73 planned moon landings and build a permanent lunar base.

The document, published April 6, is a bare-bones nine-page list of what NASA needs to achieve the "near-impossible" space plans announced March 24 at the agency's "Ignition" event.